American leaders apparently fear that by going on the record that China is the source of a huge espionage campaign there will be enormous political pressure to do something about it. The fact of the matter is that there is little you can do about it other than try to improve Internet defenses (an endless and increasingly expensive task) and talk about retaliation. But how do you retaliate? It’s historically rare for major powers to go to war just over espionage. As China points out, this Internet espionage goes both ways. But the West has a lot more to steal, compared to China, and that works to China’s advantage. China believes that the U.S. will not risk conventional combat in an effort to shut down China’s Internet hacking campaign. So far that assessment has been correct.